ES2294820T3 - DECLARATION DEVICE FOR CONSTRUCTION CONDUCTED BY PERCUTANEOUS CATETER - Google Patents

Abstract

A collapsible medical device (10) and associated method for occluding an abnormal opening in, for example, a body organ, wherein the medical device (10) is shaped from a shape memory metal fabric. The device is preferably made from a continuous tubular metal fabric and includes two outer occluding portions (12, 14), and a resilient central, spring-like interconnecting member (16). The device (10) includes a fastener (30, 32) for attaching to the end of a guide wire or delivery catheter

Description

Constriction occlusion device Percutaneous catheter driven.

I. Field of the invention

The present invention in general terms is refers to a device and a non-surgical method to treat some heart defects More particularly, the present invention relates to a low profile occlusion device for the non-surgical treatment of a patient with Foramen Ovale Perforated (FOP) resulting in cerebral embolism paradoxical. The device made according to the invention is capable of automatically adjusting a septum or septum defect with eccentric openings and fits particularly well for the transport through a catheter or located in a position distant in the heart of a patient or in an analogous vessel or organ inside a patient's body.

II. Description of the related technique

A wide variety of devices Intracardiacs are used in various medical procedures. Some intravascular devices such as catheters and guide wires, can be used to transport fluids or other devices doctors to a specific location within the heart of a patient. For example, a catheter can be used to achieve a selective coronary artery within the vascular system, or the catheter and / or guide wire can be used to place a device in an internal cavity of the patient's heart. Complex devices can be placed and used to treat specific abnormal conditions, such as the devices used to eliminate vascular occlusions or the devices used to treat wall and other similar defects.

Balloon catheters and devices prefabricated polymeric folding form similar to that discovered by Landymore and collaborators in the patent No. 4,836,204 and Linden et al. U.S. Patent No. 5,634,936 respectively have used to occlude the partition defect. When using a catheter ball similar to that described in the '204 patent, a ball is carried expandable at the distal end of said catheter. When the catheter is guided to the desired site, the ball is filled with a fluid until It occupies the glass considerably and remains in place. The resins that will harden the inside of the ball, such as acrylonitrile, can be used to permanently fix the size and shape of the ball. The ball can be uncoupled then from the end of the catheter and left in place. The device '936  it expands and hardens by a ternary system that modifies the pH and the affinity of the device for water (see patent '936, cabbage. 6, in 40-45). If these devices are not fully expand cannot be firmly placed in the defect of the septum and can rotate and release from the wall of the septum, thus freeing the bloodstream. Overfilling device '204 is an equally undesirable incident that can lead to the rupture of the ball and the discharge of the resins in the patient's bloodstream

The mechanical piston devices have proposed in the past to occlude defects in the system intravascular of a patient. The devices typically include a pair of separate patches each with an internal structure folding (similar to the structure and outer fabric of an umbrella), where the opposite patch and structure are interconnected by a joint piece The patches are typically aligned and coupled. to the common axis of the joint piece. The joint piece can be a rigid or semi-rigid cylinder that minimizes the movement of one and another patch in the lateral direction and posterior antero, thereby holds the patches firmly against the septal wall adjacent to the default. Patches that attach to the common axis of the cylinder they can cause difficulties when the defect of the septum to be occluded has eccentric openings. Since the patches are they attach to a common rigid shaft, at least one of the openings Eccentric cannot be completely covered by the patch respective. The rigid or semi-rigid hub prevents the adjustment of the patches to compensate for the eccentricity of the openings.

Representative examples of such devices mechanics are set forth in King et al., U.S. Patent No. 3,874,388 ('388 patent), Das, U.S. Patent No. 5,334,217 (patent '217), European application No. 0541.063 A2 (application '063), Sideris, U.S. Patent No. 4,917,089 (' 089 Patent), and Marks, U.S. Patent No. 5,108,420 ('420 patent). These devices are commonly preloaded in an introducer or transport catheter prior to the implantation procedure and Normally they are not placed by the doctor during the intervention. During the deployment of such devices, recovery in the transport catheter is difficult if not impossible, thereby Limit its effectiveness.

Before the implementation of these devices, the thickness of the partition wall must be determined near the defect and the approximate extent of the defect so you can Provide a device with the appropriate size. A catheter of balloon and a calibrated guide wire with opaque radius zones in length known, can be used by the doctor during a procedure preliminary fluoroscopic to estimate defect size, shape and wall thickness of the partition near the defect. Although of utility, exact size and shape of defects can not determined, therefore the possibility of leakage is increased around the occlusion device. Because of this I could a device with the inherent property of adjusting is required to the shape and thickness of the defect.

Significantly, the size of the previous devices is inherently limited by the structure and shape of the device. Also, when using occlusive devices such as those set forth in the '089,' 388, '217, or' 420 patents to occlude the partition defect, the pressure and consequently the probability of displacement of the device increases as the defect size increases. Therefore, the above devices require a larger retention cover located on each side of the defect. Often, the position of the septum defect suggests the size of the retention cover. In a defect of the membranous septum it is difficult if not unlikely to be able to position the '388,' 217, '089, or' 420 devices effectively without at least partially blocking the aorta. Also, the exposed devices tend to be quite expensive and require great time consumption in their
manufacturing.

In addition, the shape of the previous devices (for example squares, triangles, pentagons, hexagons and octagons) requires a contact area with greater surface area and it has corners that can extend to the free wall of the atria Each time the atrium contracts (approximately 100,000 times per day) the corners that extend to the walls headphones twist, creating structural fatigue cracks in 30 percent of all cases approximately. In addition, the previous devices require an introducer catheter of 14-16 French, which makes treatment impossible of children affected by birth defects with these devices. For this reason it would be advantageous to provide a device for Reliable occlusion that is easy to deploy through a catheter from 6-7 French as well as automatically adjusting to the shape and thickness of the defect. The present invention is addresses these and other disadvantages of the prior art.

Document VVO 97/42878 on which they are based the two parts of claim 1 describe a device of intravascular occlusion molded from a metallic tissue elastic, capable of adopting both the expanded form and the form collapsed The expanded form generally has the configuration of the exercise bar with two parts extended at the ends separated by a tube in the middle part.

Summary of the invention

The invention provides a medical device, folding according to claim 1. The main object of the present invention is to provide a reliable, low device profile, intracardiac occlusion device, able to adjust automatically alignment within a partition wall defect with eccentric openings, where the device is suitable for treating the defects of the septum, including the perforated oval foramen (FOP). FOP is essentially a condition characterized by an opening abnormal, wide, in the wall of the septum, between the two atria of the heart. Blood can flow directly between the two cavities, compromising the normal flow of circulation, and the efficiency of the patient's heart. Abnormal opening or defect  of the septum may not extend perpendicularly through from the wall of the septum. Rather, the center of the opening in the septum wall in the left atrium can be eccentric in relationship with the center of the opening in the wall of the septum of the right atrium, because of this "patches" are required placed eccentrically to occlude the defect effectively. Also, the wall of the septum can be very thin and require a minimum separation distance between the two "patches" occlusive The device of the present invention is formed preferably of a continuous tubular metal fabric and includes two "disks", patches, or retention covers opposite, separated and interconnected by a flexible centerpiece or elastic The centerpiece flexes both in the direction lateral as antero posterior and thus provides a tension inside against each of the discs.

When these intravascular devices are formed from an elastic metal mesh, a number of elastic wires or cables, the metallic fabric is formed by braided elastic threads to create a resistant material. This braided fabric is then deformed to adapt so general to the mold surface of a mold and said mesh braided is subjected to heat in contact with the mold surface at high temperature. The time and temperature of the treatment thermal are essentially selected to achieve deformation of the braided fabric After heat treatment, the mesh is removed of contact with the mold and will substantially retain its state of deformation. The braided fabric thus treated characterizes the state of relaxing the medical device that can stretch or expand and deploy through a catheter in a duct in The body of a patient. Those skilled in the art will appreciate that the mold cavities should reproduce the desired shape of the device and also the mold pieces are described in the U.S. application pending 5725552 filed May 14 1996, entitled "Occlusion device directed by catheter intravascular percutaneous "which is designated the same beneficiary than the present invention.

The device of the present invention has a specific way particularly satisfactory to occlude the FOP The device has a folded low profile configuration and includes rings that allow its coupling to the end of a transport device or guide wire (which allows you to recover the device after placement). During use, a guide catheter is positioned and inserted into the body of a patient, so that the distal end of the catheter is adjacent to the area where the treatment of the physiological alteration The medical device of the present invention with a predetermined form is then stretched and inserted into catheter light. The device is released through the catheter and outside the distal end, after which, due to its form memory property will tend to recover, in essence, its state of relaxation, adjacent to the treatment area. He guide wire or the transport catheter is then released from the ring and withdraws.

Objects

A main object of the present invention is,  therefore, have a suitable device for occlusion of the septum defect, capable of automatically adjusting to eccentric septum defect openings while provides internal tension in the occlusive patches of the device.

Another object of the present invention is provide a suitable device to occlude defects of the partition with eccentric openings, where the device is particularly well configured for transport through a catheter or to a distant area in the heart of a patient or in a Analog vessel or internal organ in the patient's body.

A further object of the present invention is provide an occlusive device with occlusive parts exteriors and a flexible elastic centerpiece that stabilizes the outer occlusive portions.

These and other objects, as well as these and others Features and advantages of the present invention will be made readily apparent to those skilled in the art, from a review of the detailed description that follows from the preferred embodiment, together with the claims and drawings in which the numbers in the various views refer to the corresponding parts.

Brief description of the drawings

Figure 1 is a perspective view of a permeable oval foramen occlusion device according to the present invention;

Figure 2 is a side elevation view of the medical device of the type shown in Figure 1;

Figure 3 is a partial side view in elevation of the medical device shown in figure 2, is shows partially stretched along its longitudinal axis;

Figure 4 is a side elevation view of the medical device of the type shown in Figure 3, slightly  more stretched along its longitudinal axis than in the figure 3;

Figure 5 is a side elevation view of the medical device of the type shown in Figure 4, which shows slightly more stretched along its longitudinal axis that in figure 4;

Figure 6 is a side elevation view of the medical device of the type shown in figure 1, is shown partially stretched, where the outer perimeter of the disks separated;

Figure 7 is a partial side view in elevation of the medical device of the type shown in figure 1, and is represented partially stretched by its longitudinal axis;

Figure 8 is a side elevation view of another embodiment of the present invention showing it partially stretched by its longitudinal axis;

Figure 9 is a side elevation view of another embodiment of the present invention in which it is shown partially stretched along its longitudinal axis;

Figure 10 is a side elevation view of another embodiment of the present invention in which it is shown partially extended along its longitudinal axis;

Figure 11 is a partial side view in elevation of the embodiment of figure 8 shown when it occludes a  FOP of the partition;

Figure 12 is a partial side view in elevation showing the embodiment of figure 8 in the FOP occlusion of the septum; Y

Figure 13 is a partial side view of elevation section of the embodiment of figure 1 showing occlusion of the atrial septum defect.

Detailed description of the preferred representation

The present invention provides a device of occlusion driven by a percutaneous catheter for use in the closure of an abnormal opening in a patient's body, particularly suitable to occlude a FOP (see figures 11-13). The occlusion device includes two separate parts, interconnected by a flexible central part and elastic. A ring is fixed to the outer end of each piece of occlusion, where said rings adapt to fit the end of a guide wire or catheter for transport to the site previously selected within the patient. In the realization Preferably, the occlusion device is formed from a single  continuous tubular metal fabric.

The tubular tissue is formed by a plurality of wire wires with a predetermined relative orientation between they. Those skilled in the art will appreciate that the tension and Distance of twisted wires can be varied depending of the thickness of the tissue that is required. The tubular tissue has metallic filaments which define two sets of threads, essentially parallel that usually intersect in a spiral  and alternately overlap the threads of a game on the one hand in the direction of rotation contrary to those of the other game. This tubular fabric is known in the industry as braid or cord tubular.

The degree of inclination of the wire threads (that is, the defined angle between the turns of the wire and the axis of the braid) and the tension or tension of the fabric (i.e. the number of turns or alternate crossings by the length of the unit) as well as some other factors, such as the number of wires used in a tubular cord, the size or diameter of each wire in the cord and The diameter of the cord are all of importance to determine Several important properties of the device. For example, how much greater frequency of turns and inclination of the threads of the fabric, the more the density of the wire wires in said fabric will be,  and greater the rigidity of the device. Also, a larger diameter of Each braid wire, more rigidity in the device. To have Higher wire thickness also provides the device with an area of larger wire surface, which will generally raise the tendency of the device to block the area in which it display This thrombogenicity can be increased, or it can be reduced by coating with a layer of an agent thrombolytic, or by coating with a layer of a compound antithrombogenic lubricant. When using a tubular cord to form the device of the present invention, a thread is suitable tubular approximately 4 mm in diameter that has approximately 72 twisted wires, to manufacture devices able to occlude abnormal openings, septum defects or both of them.

The strands or filaments of tissue wire Tubular metallic are preferably manufactured from alloys with the so-called shape memory. Such alloys tend to have a temperature induced phase change which will cause the material has a preference setting that can be set by heating the material above a certain temperature of transition to induce a change in the phase of the material. When the alloy cools below the transition temperature, the alloy will "remember" the shape it had during treatment thermal and will tend to assume that configuration unless it is limited To do so.

Without any intention to limit it, the suitable materials for the thread can be selected from a group consisting of cobalt alloy based on low expansion thermal described in the field as ELGELOY®, "superalloys" high strength nickel at high temperature (including nitinol) commercially available for example, at Haynes International under the trade name HASTELLOY®, nickel based alloys heat treatable, sold under the name INCOLOY® by International Nickel, and stainless steel of various grades. He important factor in selecting the right material for wire threads is that the wires retain the right amount of the deformation induced by the molding surface (as described below), when subjected to heat treatment predetermined.

In the preferred embodiment, the threads of wire are made of an alloy with shape memory, NiTi (known as nitinol) which is a nickel and titanium alloy approximately stoichiometric and may also include quantities minors of other metals to achieve the desired properties. The treatment requirements and variations in the composition of the NiTi alloy are known in the art, therefore it is not They need to be discussed here in detail. State patents United 5,067,489 (Lind) and 4,991,602 (Amplatz et al.), the methods of which are cited here for reference, discuss the use of NiTi alloys with shape memory, in guide wires. Such NiTi alloys are preferred, at least in part, because they are commercially available and more is known about the treatment of such alloys than of other alloys with the shape memory property. NiTi alloys are also very elastic and they are said to be "super elastic" or "pseudoplastic." This elasticity allows the device to the invention return to the default setting after deployment.

When molding the medical device according to the present invention, a tubular piece of metallic fabric of appropriate size is inserted into the mold, by means of which, the fabric deforms to get, in general terms, the shape of the cavities inside the mold. The shape of the cavities is such that the metallic fabric changes substantially to the shape of the desired medical device. The centers inside the cavities they can be used to mold the shape of the tissue within said cavities The ends of wire wires of metallic fabric Tubular should be fixed to prevent the metallic tissue from losing the plot. A ring or weld, as described below, can used to fix the ends of the wire threads.

During the molding procedure, an element molding can be placed inside the light of the tubular braid before insertion into the mold to further determine the molding surface If the ends of the tubular metallic fabric have already been fixed by a ring or weld, the molding element can be inserted into the light when moving the wire strands of the fabric manually and separately and inserting the molding element into the tubular tissue light. For the use of an element of molding, dimensions and dimensions can be precisely controlled shape of the finished medical device and ensures that the tissue is according to the mold cavity.

The molding element can be formed of a selected material that allows to destroy or remove said molding element inside the metal fabric. For example, The molding element can be formed of a brittle material or friable. Once the material has been heat treated in contact with the mold cavities and the molding element, said element can be broken into smaller pieces and easily removed from The interior of the woven metal. For example, if this material is glass, molding element and metallic fabric can bang against a hard surface, which shatters the glass. The glass fragments can then be removed from the fence Attached woven metal.

Alternatively, the molding element it can be formed by a material that can dissolve easily or otherwise, chemically altered by a chemical agent that does not substantially and adversely affect the properties of the threads of metallic wire For example, the molding element can be made with a temperature resistant plastic resin, capable of dissolve with the appropriate organic solvent. In this case, the metallic fabric and the molding element can undergo a heat treatment to substantially configure the shape of the fabric in accordance with the mold cavity and the element of molding, after which, the molding element and tissue Metallic can be placed on the surface of the solvent. Once the molding element has substantially dissolved, the tissue Metallic can be removed from the solvent.

Care must be taken to ensure that materials selected to form the molding element be capable of resisting heat treatment without losing its shape, by at least until the shape of the tissue has been configured. By For example, the molding element could be formed of a material with a melting point above the temperature needed to achieve the shape of the wire wires, but below the point of fusion of the metal that forms the threads. The molding element and the metallic tissue could then be heat treated to shape to the metallic fabric, after which, the temperature is would increase until essentially the fusion of the element of molding, while the molding element would be removed from the inside the metal fabric.

Those skilled in the art will appreciate that the specific form of the molding element produces the specific form of the molded device. If a more complex form is desired, the Molding element and mold may have additional parts even aggregates that transmit movement (cam type), but if the Shape is simpler, the mold may have few pieces. The number of pieces in a given mold and the shapes of those parts will be determined almost completely by the shape of the medical device desired for which, generally, the metallic tissue is conform to.

When the tubular braid, for example, is folded in its preformed lax configuration, each of the threads of wire that form the tubular braid will have, with respect to the others, the default relative orientation first. As the tubular braid is compressed along its axis, the tissue will tend to expand outside the axis to configure with the shape of the mold. When the fabric deforms like this, the orientation will change  relative of the wire wires of the metallic fabric itself. When the mold is assembled, the metal fabric is usually will conform to the molding surface inside the cavity. After suffering the shape memory process, the device resulting doctor has a relaxed or lax setting preset and a folded or extended configuration that allows to pass the device through a catheter or other transport device Similary. The relaxed configuration is usually defined by the tissue shape when deformed in general terms conform to the mold molding surface.

Once the flat or tubular metallic fabric is properly positioned inside a pre-selected mold with the metal fabric usually adjusted to the molding surface of the cavities in question, the tissue can undergo a heat treatment while remaining in contact with the molding surface The proper heat treatment process to configure the nitinol wire in the desired way it is known Fine in the art. Nitinol braids rolled in the form of spiral for example, are used in a number of medical devices, such as in the formation of commonly carried rings around the distal junctions of the guide wires. There is ample knowledge in nitinol formation in such devices as well it is not necessary to treat treatment parameters thoroughly thermal for nitinol tissue selected for use in the present invention Briefly, however, it has been shown that subjecting the nitinol tissue at approximately temperature from 500 to 550 degrees Celsius for an approximate period of 1 to 30 minutes and depending on the softness or hardness of the device that needs to be done, will tend to configure the tissue in its state of deformity, that is, as conformed in the Molding surface of mold cavities. At more temperatures low, the heat treatment time will tend to be longer (for example, about 1 hour at about 350 degrees Celsius) and at higher temperatures the weather will tend to be shorter (for example, approximately 30 seconds at a temperature close to 900 degrees Celsius). These conditions can be varied as necessary to adjust the variations in the exact composition of the Nitinol, prior to its heat treatment, the properties of Nitinol desired in the finished article and other factors known by experts in this field.

Instead of relying on thermal convection or similar methods are also known in the art the application of an electric current to nitinol to heat it. At the moment invention, this can be achieved for example by connecting electrodes at each end of the metallic tissue. Wire can then be heated by the heating resistance of said wires to achieve the desired heat treatment, which will tend to eliminate the need to apply heat to the entire mold in the magnitude required to heat the metallic fabric as want. Materials, molding elements and molding methods a medical device from a tubular or flat metallic tissue They are further described in U.S. Patent Application Serial No. 08 / 647,712, filed on May 14, 1996 and assigned to it assignee than the present invention, and published as US-A-5725552.

The heat treatment of the metallic fabric a temperatures ranging between 500-550 degrees centigrade essentially configures the shapes of the threads of wire in a reoriented relative position that adjusts the shape from the fabric to the molding surface. When the metallic fabric gets removed from the mold, the fabric maintains the shape of the surfaces of molding of the mold cavities to define a device doctor with certain form. After heat treatment, the tissue is removed from contact with the molding cavity and It will essentially retain its deformed state. If a molding element, said molding element can be removed as described above

The time required for the process of heat treatment will depend mainly on the material from which  they form the wires of wire, of the metallic fabric and the mass of the mold, but the time and temperature of the heat treatment must be selected to substantially configure the tissue in your state of deformity, that is, where the wire wires are reoriented in their relative configuration and generally tissue It conforms to the molding surface. The time required and the heat treatment temperature can vary greatly and They depend on the material used to form the wire wires. As mentioned above, the kind of materials that are prefer to form wire strands are alloys with shape memory like nitinol, a titanium and nickel alloy, which particularly preferred. If nitinol is used to make woven wire threads, these will tend to be very elastic when the metal is in its austenitic phase; to this phase so elastic has frequently been known as a phase superelastic or pseudoplastic. Heating the nitinol above the transition temperature of a certain phase, the structure crystalline nitinol metal, will tend to "take" the shape of the fabric and the relative configuration of the wire strands in the positions in which they are maintained during treatment thermal.

Once the device has been formed with a by default, said device can be used to treat the dysfunctional state of a patient. A Medical device suitable to treat the condition. Once the appropriate medical device is selected, a catheter or other device equally suitable for transport can position itself inside a duct in the patient's body to place the distal end of the adjacent transport device to the aforementioned treatment zone, such as the communication of a Abnormal opening immediately adjacent (or even inside) in the patient organ, for example.

The transport device (not shown) can take a proper indeterminate form, but desirably consists of an elongated and flexible metal shaft with a distal end screwed. The transport instrument can be used to drive the medical device through the light of a catheter for the deployment in the duct of a patient's body. When he device is deployed outside the distal end of the catheter, the device will still be retained by the transport instrument. A Once the medical device is properly positioned within the abnormal opening communication, the distal end of the catheter can be pressed against the medical device and the metal body or guide wire can be rotated on its axis to unscrew the medical device from the threaded distal end of the shaft. So the catheter and guide wire are removed.

By keeping the medical device attached to the means of transport means that the operator can retract the device to relocate it in relation to the abnormal opening, if it is determined that the device is not properly placed within the communication A threaded ring coupled to the device doctor allows the operator to control the way in which the medical device is deployed outside the distal end of the catheter. When the device leaves the catheter, it will tend to recover, by elasticity, the relaxed form chosen. When the device It adopts its previous form, it can tend to touch against the end distal catheter and effectively lead yourself beyond the catheter end This spring effect could probably produce improper positioning of the device if the location of the device inside the duct is at one point critical, such as when it is positioned in a communication between two glasses. Since the threaded ring can allow the operator keep the device held during deployment, the effect device spring can be controlled by the operator to ensure proper positioning during deployment.

The medical device can be folded to your folded configuration and inserted into catheter light. The Folded device configuration can be any way,  suitable for easy passage through the light of a catheter and proper deployment outside the distal end of the catheter. By for example, the occlusive device for FOP may have a relatively elongated folded configuration where the device stretches along its longitudinal axis (see Figure 5). This folded configuration can be achieved simply by stretching the device generally along its axis, for example, taking the rings with your hands and pulling them separately, which will tend to fold the relaxed parts of the diameter of the device internally towards the axis of said device. Loading such a device into a catheter can be done. at the time of implementation what does not require preload the introducer or catheter.

If the device will be used to occlude permanently a duct in the patient's body, simply  The catheter can be retracted and removed from the patient's body. This leaves the medical device deployed in the vascular system. of the patient so that he can occlude the blood vessel or other duct  in the patient's body. In some circumstances, the medical device can be coupled to a transportation system, in such a way that the device is secured to the end of the transport. Before removing the catheter in such a system, it may be necessary to separate the medical device from the means of transport before removing the catheter and the means of transport.

When the device is deployed in a patient, there will be a tendency to thrombus formation in the wire surface. By having the wires thicker, the total surface area of the wires will increase, thus increasing the thrombotic activity of the device which it allows you relatively quickly to occlude the vessel in which it display It is thought that by forming the occlusion device a from a tubular braid with a diameter of 4 mm with an amount of turns of at least 40 and an inclination angle of at least 30º approximately, the surface area will be provided enough to essentially and completely occlude the abnormal opening of the partition. If you want to increase the proportion to which the device occludes, any of a variety can be applied to the device wide of known occlusion agents. Those skilled in the art they will appreciate that an occlusive membrane, fiber, or mesh can position within any of discs 12 and 14 or both, to further improve the occlusive characteristic of each disc (see Figure 3).

Finished the detailed description of the invention, the specific reference to the figures will be presented to continuation. The various figures illustrate various embodiments of the invention where the central part is elastic and pulls the outer disks, from one to the other. In relation first to Figures 1 and 2, the device 10 is generally shown suitable to occlude the Permeable Oval Foramen (FOP). In state of relaxation, not extended (see Figure 2), device 10 generally includes two aligned 12 and 14 discs attached to each other another for an elastic central portion 16. The number of wires braided form the outer surface 18 and inner 20 of each disk. The inner surface 20 of each disk can be concave or cup-shaped (also see Figure 7) to ensure that the edge of the outer perimeter 22 and 24 of each disk 12 and 14 be put in contact with the wall of the corresponding partition 40.

When device 10 is in the state of relaxation, discs 12 and 14 tend to overlap and the portion central 16 extends in the vacuum formed by the internal surface of disks 12 and 14. Thus, when disks 12 and 14 are separate (see Figure 3) the spring effect of the central portion 16 will cause the edge of perimeter 22 and 24 of the disk corresponding fully close the side wall of the partition (see Figure 11 and 12). Figures 3-5 illustrate of sequential mode stretching by the spring effect of the portion 16 central curved. Without intentional limitations, during the formation of device 10, the braid is partially flattened tubular (in the region that forms the central portion 16) to improve the spring effect in said central portion16. Figure 6 illustrates that discs 12 and 14 can be balanced laterally by stretching of the central portion 16.

The ends 26 and 28 of the tubular metal fabric twisted device 10 are welded or held together with the corresponding rings 30 and 32 to prevent fraying. By course, alternatively, the ends can be joined without difficulty by other means that are known by experts in the technique. In addition, it is understood that other fixing means suitable can be coupled to ends 26 and 28 in other ways, as heat welding, welding with a point alloy low, or high melting, or with the use of cement material biocompatible, or in any other useful way. Rings 30 and 32 that hold wire wires together at the ends corresponding 26 and 28 also serve to connect the device to a transport system. In the realization that has been shown, rings 30 and 32 are generally cylindrical in shape and have an internal diameter 34 threaded (see Figure 7) to receive the ends 26 and 28 of the metallic fabric and essentially prevent the relative movement of some wires with others. The interior 34 threaded adapts to receive and lock the distal end as well Threading of a transport device.

Figures 8-10 show additional embodiments of device 10 where the shape of the central elastic portion 16 is varied. The central part 16 is flexible in both directions, lateral and antero posterior. This flexibility gives the device the characteristic of focus on yourself, whereby, disks 12 and 14 tend to automatically center themselves around the opening adjacent to the defect (see Figures 11 and 12) while tending to throw the discs, towards each other. The central portion 16 may include a coil-like helical shape (see figure 9), a spiral shape (see figure 10), or a shape curved (see figure 2).

Those skilled in the art will appreciate that the device 10 is classified according to the size of the communication interatrial to be occluded. The diameter of each disc 12 and 14 can be varied as desired for the wall openings of the septum classified differently according to size. Besides, the length of the central elastic portion can also be varied in Dependence on the wall thickness of the partition, and can range from 4 to 40 mm

The device 10 for FOP occlusion can be advantageously done according to the summarized method previously. The device is preferably made of a mesh 0.013 cm nitinol wire. The braided mesh wire can be carried out with 28 alternate crosses per inch with an inclination angle of approximately 64 degrees when Use a Maypole braider with 72 wire strands. The rigidity of the device 10 for FOP can be increased or decreased when changing the wire size, the angle of inclination, the number of alternate crosslinks, the diameter of the braid, the number of wire filaments, or the treatment process thermal. Those skilled in the art will recognize the discussion precedent that the mold cavities must be configured in correspondence with the form of the device for FOP that want.

When using untreated NiTi fabrics, the threads they will tend to return to their unbraided configuration and the cord can untangle fairly quickly unless the ends of the Braid length be constrained to each other. Rings 30 and 32 are useful to prevent the braid from unraveling in any of the ends, thus effectively define an empty space inside of the sealed end of the fabric. These rings, 30 and 32, keep the ends of the braid cuts attached and prevent that said Braid falls apart. Although welding with low and high point of NiTi alloy fusion has proven to be quite difficult, the ends can be welded together, both by melting the wires or with a laser welder. When cutting the fabric to the dimensions desired, care should be taken to ensure that the tissue is not undo In the case of tubular braids for example, formed of NiTi alloys, the individual threads will tend to return to their configuration obtained by the action of heat unless it they constrain. If the braid is subjected to heat to configure the braided strands, these will tend to remain in the form braided and only the ends will fray. However, it can be cheaper to simply form the braid without heat treatment of said braid, since the fabric will be treated again with heat to form the medical device.

The use of the device 10 of the present invention will now be discussed in greater detail in relation to the occlusion of a FOP. The device can be transported and placed adequately with the use of two-dimensional echocardiography and a color Doppler flow mapping. As indicated previously, the transport instrument can take the form suitable, whatever, preferably consisting of an axis stretched flexible metal similar to a conventional guide wire. He transport instrument is used to carry the device FOP occlusion through the diameter cylindrical tube light small, as is a transport catheter, for the deployment of said device. The FOP device 10 is placed in the tube Small diameter cylindrical using a charging case to stretch the device and put it in its elongated configuration or stretched out The device can be inserted into the tube light during the procedure or can be pre-assembled as a facility for the manufacture, in which the devices of the present invention they do not remain placed when they are kept in state compressed.

From the approach through the femoral vein, the catheter or transport tube is passed through the FOP. Device 10 is advanced through the transport catheter to the end distal, return to the unconstrained state to exit to the end of the catheter, after which it assumes its disk shape in the atrium left (see figure 13). The transport catheter is pulled then back in the proximal direction through the FOP and the transport instrument is also pulled proximally, pushing the distal disc against the septum. Catheter of transport is then pulled further out from the partition, allowing that the proximal disc extends outside the transport catheter where by resilience it returns to its default form of loose disk. From In this way, the FOP device is positioned such that the distal disc presses against the side of the septum while the Proximal disc presses against the other side of the septum. For increase its occlusion capacity, the device may contain polyester fibers or nylon fabric (see figure 3). In the cases where the device is improperly deployed in a First test, can be recovered by pulling the device transport in the proximal direction, to retract the device 10 inside the transport catheter prior to a second attempt to position the device in relation to the defect.

When the FOP occlusion device is placed properly, the doctor turns the guide wire, to separate the  distal end of said guide wire of ring 30 or 32 of the occlusion device 10. The threads in the ring are such that the guide wire rotation unscrews the ring guide wire of occlusion device 10, instead of simply rotating the occlusion device As noted previously, the ring threaded can also allow the operator to hold the device during deployment, or allows the operator to control the spring effect during device deployment to ensure proper positioning.

This invention has been described in this document. in sufficient detail to comply with the EPC and to provide those skilled in the art the information they need to apply the new principles and build and use realizations of example as required. However, it will be understood that the invention can be performed on specifically different devices and that several modifications can be carried out without deviating from the scope of said invention as defined by the following claims.

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References cited in the description

This list of references cited by the Applicant is only for the convenience of the reader. Not a part  of the European Patent document. Even when you have had great Be careful when compiling references, errors or omissions cannot be excluded and the EPO denies all Responsibility in this regard.

Patent documents cited in the description

US 4836204 A, Landymore [0003]

US 5108420 A [0005]

US 5634936 A, Linde [0003]

US 5725552 A, [0011] [0032]

US 3874388 A, King [0005]

US 5067489 A, Lind [0023]

US 5334217 A [0005]

US 4991602 A, Amplatz [0023]

EP 0541063 A2 [0005]

US 64771296 A [0032]

US 4917089 A [0005]

Claims (6)

1. A folding medical device (10) for occlusion, consisting in its folded condition, of two parts with expanded diameter (12, 14) and an unfolded elastic central portion (16) that interconnects the two parts of expanded diameter, said device it has a proximal and a distal end, which are formed in said device from a continuous metal tubular fabric consisting of a plurality of interwoven metal wires and, in which at least one of the proximal and distal ends includes means for fixing said device to a transport system, said device is reversibly deformable to a folded configuration for transport through a conduit in a patient's body, characterized in that the elongated central elastic portion (16), in its folded form, is configured so that it does not remain straight and therefore to form an elastic portion that consequently pulls the two expanded diameter parts (12, 14), a to the other. 2. The device, as stated in the claim 1, wherein each expanded diameter part (12, 14) It has an internal surface and an external surface (20, 18) deforms such that the internal surfaces face each other, and the internal surface of at least one of the diameter parts expanded is at least partially concave. 3. The medical device as stated in the claim 1, wherein the inner surface (20) of the first portion with expanded diameter (12) is at least partially concave, and a length of the central elastic portion (16) is sized such that an edge of the perimeter (22) of the first portion with expanded diameter overlaps the edge of the perimeter (24) of a second portion with expanded diameter (14). 4. The medical device as stated in the claim 1, wherein said parts (30,32) for fixing, include the means (34) for fixing to a device transport. 5. The medical device as stated in the claim 1, wherein said elastic central portion It is helical, spiral or curved. 6. The folding medical device of the claim 1, each of the proximal and distal ends (28, 26) having means (30, 32) to fix the metal fabric attached to these, and thus preventing tissue fraying metal.